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A metal surface is exposed to light with wavelengths of 248 nm and 310 nm. The maximum velocities of the emitted photoelectrons for these wavelengths are v₁ and v₂, respectively. Given that the ratio v₁: v₂ is 2: 1 and hc = 1240 eV·nm, estimate the work function of the metal.

1. 3.7 eV
2. 3.2 eV
3. 2.8 eV
4. 2.5 eV

Correct answer: 3.7 eV

Solution

The correct answer is 3.7 eV because we can use the Einstein photoelectric effect equation to estimate the work function of the metal, given the ratio of the maximum velocities of the emitted photoelectrons and the wavelengths of the light.

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